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1.
Bioorg Chem ; 92: 103263, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31536953

RESUMO

α-Methylacyl-CoA racemase (AMACR; P504S) catalyses an essential step in the degradation of branched-chain fatty acids and the activation of ibuprofen and related drugs. AMACR has gained much attention as a drug target and biomarker, since it is found at elevated levels in prostate cancer and several other cancers. Herein, we report the synthesis of 2-(phenylthio)propanoyl-CoA derivatives which provided potent AMACR inhibitory activity (IC50 = 22-100 nM), as measured by the AMACR colorimetric activity assay. Inhibitor potency positively correlates with calculated logP, although 2-(3-benzyloxyphenylthio)propanoyl-CoA and 2-(4-(2-methylpropoxy)phenylthio)propanoyl-CoA were more potent than predicted by this parameter. Subsequently, carboxylic acid precursors were evaluated against androgen-dependent LnCaP prostate cancer cells and androgen-independent Du145 and PC3 prostate cancer cells using the MTS assay. All tested precursor acids showed inhibitory activity against LnCaP, Du145 and PC3 cells at 500 µM, but lacked activity at 100 µM. This is the first extensive structure-activity relationship study on the influence of side-chain interactions on the potency of novel rationally designed AMACR inhibitors.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Racemases e Epimerases/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Masculino , Estrutura Molecular , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Racemases e Epimerases/metabolismo , Relação Estrutura-Atividade
2.
Bioorg Chem ; 92: 103264, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31536955

RESUMO

α-Methylacyl-CoA racemase (AMACR; P504S; EC 5.1.99.4) catalyses epimerization of 2-methylacyl-CoAs and is important for the degradation of branched-chain fatty acids and the pharmacological activation of ibuprofen and related drugs. It is also a novel drug target for prostate and other cancers. However, development of AMACR as a drug target has been hampered by the difficulties in assaying enzyme activity. Consequently, reported inhibitors have been rationally designed acyl-CoA esters, which are delivered as their carboxylate prodrugs. The novel colorimetric assay for AMACR based on the elimination of 2,4-dinitrophenolate was developed for high-throughput screening and 20,387 'drug-like compounds' were screened, with a throughput of 768 compounds assayed per day. Pyrazoloquinolines and pyrazolopyrimidines were identified as novel scaffolds and investigated as AMACR inhibitors. The most potent inhibitors have IC50 values of ~2 µM. The pyrazoloquinoline inhibitor 10a displayed uncompetitive inhibition, whilst 10j displayed mixed competitive inhibition. The pyrazolopyrimidine inhibitor 11k displayed uncompetitive inhibition. This is the first report of the identification of specific drug-like small-molecule AMACR inhibitors by high-throughput screening. Pyrazoloquinolines and pyrazolopyrimidines may also be useful as inhibitors of other CoA-utilizing enzymes.


Assuntos
Inibidores Enzimáticos/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Quinolinas/farmacologia , Racemases e Epimerases/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Colorimetria , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Ensaios de Triagem em Larga Escala , Humanos , Estrutura Molecular , Pirazóis/síntese química , Pirazóis/química , Pirimidinas/síntese química , Pirimidinas/química , Quinolinas/síntese química , Quinolinas/química , Racemases e Epimerases/metabolismo , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
3.
Curr Osteoporos Rep ; 17(6): 510-520, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31734907

RESUMO

PURPOSE OF REVIEW: This review sought to describe quality improvement initiatives in fragility fracture care and prevention. RECENT FINDINGS: A major care gap persists throughout the world in the secondary prevention of fragility fractures. Systematic reviews have confirmed that the Fracture Liaison Service (FLS) model of care is associated with significant improvements in rates of bone mineral density testing, initiation of osteoporosis treatment and adherence with treatment for individuals who sustain fragility fractures. Further, these improvements in the processes of care resulted in significant reductions in refracture risk and lower post-fracture mortality. The primary challenge facing health systems now is to ensure that best practice is delivered effectively in the local healthcare setting. Publication of clinical standards for FLS at the organisational and patient level in combination with the establishment of national registries has provided a mechanism for FLS to benchmark and improve their performance. Major efforts are ongoing at the global, regional and national level to improve the acute care, rehabilitation and secondary prevention for individuals who sustain fragility fractures. Active participation in these initiatives has the potential to eliminate current care gaps in the coming decade.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Osteoporose/diagnóstico , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/terapia , Melhoria de Qualidade , Encaminhamento e Consulta , Gerenciamento Clínico , Humanos , Fraturas por Osteoporose/prevenção & controle , Guias de Prática Clínica como Assunto , Prevenção Secundária
4.
J Biol Chem ; 288(29): 21126-21135, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23760261

RESUMO

It is now recognized that innate immunity to intestinal microflora plays a significant role in mediating immune health, and modulation of microbial sensing may underpin the impact of plant natural products in the diet or when used as nutraceuticals. In this context, we have examined five classes of plant-derived flavonoids (flavonols, flavones, flavanones, catechins, and cyanidin) for their ability to regulate cytokine release induced by the Toll-like receptor 2 (TLR2) agonist Pam3CSK4. We found that the flavonols selectively co-stimulated IL-1ß secretion but had no impact on the secretion of IL-6. Importantly, this costimulation of TLR2-induced cytokine secretion was dependent on regiospecific methylation of the flavonol scaffold with a rank order of quercetin-3,4'-dimethylether > quercetin-3-methylether > casticin. The mechanism underpinning this costimulation did not involve enhanced inflammasome activation. In contrast, the methylated flavonols enhanced IL-1ß gene expression through transcriptional regulation, involving mechanisms that operate downstream of the initial NF-κB and STAT1 activation events. These studies demonstrate an exquisite level of control of scaffold bioactivity by regiospecific methylation, with important implications for understanding how natural products affect innate immunity and for their development as novel immunomodulators for clinical use.


Assuntos
Flavonoides/química , Interleucina-1beta/biossíntese , Monócitos/metabolismo , Receptor 2 Toll-Like/metabolismo , Caspase 1/metabolismo , Linhagem Celular , Cicloeximida/farmacologia , Sinergismo Farmacológico , Flavonoides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Lipopeptídeos/farmacologia , Metilação/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , Fosforilação/efeitos dos fármacos , Quercetina/análogos & derivados , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estereoisomerismo , Receptor 2 Toll-Like/agonistas , Transcrição Gênica/efeitos dos fármacos
5.
Curr Osteoporos Rep ; 11(1): 52-60, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23334619

RESUMO

Fracture Liaison Services (FLS) have been demonstrated in many countries to provide an effective means to deliver secondary preventive care for patients presenting with fragility fractures. This review provides an update on journal articles, reports, guidelines and government policies, with relevance to FLS, which have been published during the period 2009-2012. International evidence of the extent and persistence of the secondary fracture prevention care gap has expanded during this period. Major professional and patient societies throughout the world, including the International Osteoporosis Foundation and the American Society for Bone and Mineral Research, have supported international initiatives to disseminate best practice. Health economic analysis of FLS has developed considerably, with a consistent theme from investigator-led and government analyses that FLS provide highly cost-effective care. Opportunities to close the care gap, in a systematic way, for unrecognised vertebral fracture sufferers are also considered.


Assuntos
Osteoporose/complicações , Fraturas por Osteoporose/prevenção & controle , Padrões de Prática Médica/tendências , Prevenção Secundária/tendências , Análise Custo-Benefício , Gerenciamento Clínico , Humanos , Incidência , Cooperação Internacional , Osteoporose/economia , Fraturas por Osteoporose/economia , Fraturas por Osteoporose/epidemiologia , Padrões de Prática Médica/economia , Prevenção Secundária/economia
6.
Curr Osteoporos Rep ; 11(4): 377-84, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24026314

RESUMO

Fracture Liaison Services (FLS) have been demonstrated to be a clinically and cost-effective means of providing secondary preventive care for patients presenting with new fragility fractures. This review summarizes the emergence and widespread adoption of the FLS model in the United Kingdom. Large scale national audits have clearly illustrated the need for FLS by revealing the care gap experienced by the majority of patients who suffer fragility fractures. Since 2003, FLS has featured increasingly more prominently in relevant national professional guidance. During the last 5 years that professional consensus has led to FLS being embedded in government policy on fracture prevention. Quality incentives have been created to encourage hospitals and primary care providers to pro-actively deliver best practice. The strategic approaches taken and lessons learned in the UK may have relevance to quality improvement efforts in other jurisdictions.


Assuntos
Atenção à Saúde , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/terapia , Análise Custo-Benefício , Atenção à Saúde/economia , Gerenciamento Clínico , Humanos , Fraturas por Osteoporose/prevenção & controle , Qualidade da Assistência à Saúde/normas , Prevenção Secundária , Reino Unido/epidemiologia
7.
J Bone Miner Res ; 37(4): 608-615, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35279864

RESUMO

In the Asia Pacific (AP) region, osteoporosis and its consequence of fragility fractures are not widely recognized as a major public health problem. Several challenges including underdiagnosis and undertreatment exist. The Asia Pacific Consortium on Osteoporosis (APCO) is a nonpartisan and apolitical organization comprising musculoskeletal experts and stakeholders from both private and public sectors who have united to develop tangible solutions for these substantive challenges. APCO's vision is to reduce the burden of osteoporosis and fragility fractures in the AP region. Heterogeneity in both scope and recommendations among the available clinical practice guidelines (CPGs) contribute to the large osteoporosis treatment gap in the Asia Pacific. APCO has therefore developed a pan Asia-Oceania harmonized set of standards of care (The Framework), for the screening, diagnosis, and management of osteoporosis. First, a structured analysis of the 18 extant AP CPGs was completed. Subsequently, a prioritization of themes and agreement on fundamental principles in osteoporosis management were made through a Delphi process of consensus building. This approach, ensuring the opinions of all participating members were equally considered, was especially useful for a geographically diverse group such as APCO. It is hoped that the Framework will serve as a platform upon which new AP national CPGs can be developed and existing ones be revised. APCO is currently embarking on country-specific engagement plans to embed the Framework in clinical practice in the AP region. This is through partnering with regulatory bodies and national guidelines development authorities, through peer-to-peer health care professional education and by conducting path finder audits to benchmark current osteoporosis services against the Framework standards. The principles underpinning the harmonization of guidelines in the AP region can also be utilized in other parts of the world that have similar socioeconomic diversity and heterogeneity of healthcare resources. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).


Assuntos
Fraturas Ósseas , Osteoporose , Ásia/epidemiologia , Benchmarking , Humanos , Programas de Rastreamento , Osteoporose/diagnóstico , Osteoporose/tratamento farmacológico , Osteoporose/epidemiologia
8.
J Transl Med ; 7: 4, 2009 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-19138409

RESUMO

BACKGROUND: Recently, nanometer sized vesicles (termed exosomes) have been described as a component of urine. Such vesicles may be a useful non-invasive source of markers in renal disease. Their utility as a source of markers in urological cancer remains unstudied. Our aim in this study was to investigate the feasibility and value of analysing urinary exosomes in prostate cancer patients undergoing standard therapy. METHODS: Ten patients (with locally advanced PCa) provided spot urine specimens at three time points during standard therapy. Patients received 3-6 months neoadjuvant androgen deprivation therapy prior to radical radiotherapy, comprising a single phase delivering 55 Gy in 20 fractions to the prostate and 44 Gy in 20 fractions to the pelvic nodes. Patients were continued on adjuvant ADT according to clinical need. Exosomes were purified, and the phenotype compared to exosomes isolated from the prostate cancer cell line LNcaP. A control group of 10 healthy donors was included. Serum PSA was used as a surrogate treatment response marker. Exosomes present in urine were quantified, and expression of prostate markers (PSA and PSMA) and tumour-associated marker 5T4 was examined. RESULTS: The quantity and quality of exosomes present in urine was highly variable, even though we handled all materials freshly and used methods optimized for obtaining highly pure exosomes. There was approx 2-fold decrease in urinary exosome content following 12 weeks ADT, but this was not sustained during radiotherapy. Nevertheless, PSA and PSMA were present in 20 of 24 PCa specimens, and not detected in healthy donor specimens. There was a clear treatment-related decrease in exosomal prostate markers in 1 (of 8) patient. CONCLUSION: Evaluating urinary-exosomes remains difficult, given the variability of exosomes in urine specimens. Nevertheless, this approach holds promise as a non-invasive source of multiple markers of malignancy that could provide clinically useful information.


Assuntos
Biomarcadores Tumorais , Exossomos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Adulto , Idoso , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/química , Biomarcadores Tumorais/urina , Linhagem Celular Tumoral , Exossomos/química , Exossomos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Resultado do Tratamento
10.
J Bone Miner Res ; 27(10): 2039-46, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22836222

RESUMO

Fragility fractures are common, affecting almost one in two older women and one in three older men. Every fragility fracture signals increased risk of future fractures as well as risk of premature mortality. Despite the major health care impact worldwide, currently there are few systems in place to identify and "capture" individuals after a fragility fracture to ensure appropriate assessment and treatment (according to national guidelines) to reduce future fracture risk and adverse health outcomes. The Task Force reviewed the current evidence about different systematic interventional approaches, their logical background, as well as the medical and ethical rationale. This included reviewing the evidence supporting cost-effective interventions and developing a toolkit for reducing secondary fracture incidence. This report presents this evidence for cost-effective interventions versus the human and health care costs associated with the failure to address further fractures. In particular, it summarizes the evidence for various forms of Fracture Liaison Service as the most effective intervention for secondary fracture prevention. It also summarizes the evidence that certain interventions, particularly those based on patient and/or community-focused educational approaches, are consistently, if unexpectedly, ineffective. As an international group, representing 36 countries throughout Asia-Pacific, South America, Europe, and North America, the Task Force reviewed and summarized the international data on barriers encountered in implementing risk-reduction strategies. It presents the ethical imperatives for providing quality of care in osteoporosis management. As part of an implementation strategy, it describes both the quality improvement methods best suited to transforming care and the research questions that remain outstanding. The overarching outcome of the Task Force's work has been the provision of a rational background and the scientific evidence underpinning secondary fracture prevention and stresses the utility of one form or another of a Fracture Liaison Service in achieving those quality outcomes worldwide. © 2012 American Society for Bone and Mineral Research.


Assuntos
Comitês Consultivos , Fraturas Ósseas/prevenção & controle , Relatório de Pesquisa , Sociedades Médicas , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Humanos
11.
Eur Neuropsychopharmacol ; 19(12): 876-86, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19651495

RESUMO

Retinoids, vitamin A related compounds, have an established role in the development of the nervous system and are increasingly recognized to play a role in adult brain function. The synthetic retinoid, 13-cis-retinoic acid (13-cis-RA, Roaccutane) is widely used to treat severe acne but has been linked to an increased risk of neuropsychiatric side effects, including depression. Here we report that chronic administration with 13-cis-RA (1 mg/kg i.p. daily, 7-14 days) in adult rats reduced aggression- and increased flight-related behaviours in the resident-intruder paradigm. However, in the forced swim, sucrose consumption and open field tests treatment for up to 6 weeks with 13-cis-RA did not modify behaviour in adult or juvenile animals. The behavioural change observed in the resident-intruder paradigm is directly opposite to that observed with chronic antidepressant administration. These findings indicate that when a suitably sensitive behavioural test is employed then chronic administration of 13-cis-RA in adult rats induces behavioural changes consistent with a pro-depressant action.


Assuntos
Agressão/efeitos dos fármacos , Depressão/fisiopatologia , Fármacos Dermatológicos/farmacologia , Isotretinoína/farmacologia , Fatores Etários , Análise de Variância , Animais , Depressão/induzido quimicamente , Fármacos Dermatológicos/administração & dosagem , Modelos Animais de Doenças , Esquema de Medicação , Reação de Fuga/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Preferências Alimentares/efeitos dos fármacos , Isotretinoína/administração & dosagem , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar , Sacarose/administração & dosagem , Edulcorantes/administração & dosagem , Natação/psicologia , Fatores de Tempo
12.
J Immunol ; 173(1): 151-6, 2004 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15210769

RESUMO

The importance of T cell Ag specificity and Th1 vs Th2 phenotype in synovial inflammation remains controversial. Using OVA-specific TCR transgenic T cells from DO11.10 mice, we demonstrate that mice receiving Th1, but not Th2, cells display a transient arthritis following immunization that is characterized by synovial hyperplasia, cellular infiltration, and cartilage erosion. OVA-specific T cells also accumulated in inflamed joints, suggesting that they could exert their inflammatory effect locally in the joint or in the draining lymph node. Importantly, this pathology was accompanied by a breakdown in self-tolerance, as evidenced by the induction of collagen-specific T and B cell responses. This model directly demonstrates a pivotal role for Th1 cells of an irrelevant specificity in the development of inflammatory arthritis. Furthermore, the ability to track these cells in vivo will make feasible studies revealing the dynamic role of T cells in arthritis.


Assuntos
Artrite Experimental/imunologia , Tolerância Imunológica , Articulações/imunologia , Ovalbumina/imunologia , Receptores de Antígenos de Linfócitos T/fisiologia , Linfócitos T/imunologia , Animais , Formação de Anticorpos , Artrite Experimental/etiologia , Células Cultivadas , Colágeno Tipo II/imunologia , Citocinas/biossíntese , Imuno-Histoquímica , Imunofenotipagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C
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